Babel: Drama. Starring Brad Pitt, Cate Blanchett, Adriana Barraza and Rinko Kikuchi. Directed by Alejandro González Iñárritu. (R. 142 minutes. In English, in Japanese with English subtitles and in Moroccan Arabic with English subtitles. At Bay Area theaters.)

"Babel" follows four stories simultaneously, in a fractured narrative intended to illuminate a single event: a shooting in Morocco. It's a film of unquestioned visual artistry, and the filmmakers' empathy and human understanding are apparent moment to moment, scene by scene.

But despite sensitive performances, it's an experiment that fizzles. The stop-and-start storytelling strategy doesn't just make the film frustrating to watch. It also promises a payoff that never arrives.

In the end, a film of profound ambition is unmasked as one without real purpose, a misguided attempt to make a serious, important statement despite having nothing, really, to say. In "21 Grams," director Alejandro González Iñárritu and screenwriter Guillermo Arriaga went back and forth in time, following multiple characters because that was the best way to enrich and explore the story. In "Babel," the same filmmakers take a similarly experimental approach because, well, maybe because it worked in "21 Grams."

Of the four stories covered in this long film, only one is genuinely compelling, and two have very little to do with the film's main incident. Sure, between all of them there are causal connections to be made -- someone in Japan does something and as a result something else ends up happening to a Mexican woman living in San Diego.

But the connections are just a matter of happenstance. They don't have the quality of inevitability that would make the film into a genuine comment on language and culture (as hinted at by the title), nor do the connections lend the individual stories any extra meaning.

In a rural village in Morocco, a goat herder buys a high-powered rifle and instructs his two young sons to go out and kill jackals. Instead, they take aim at a bus full of Western tourists.

Meanwhile in Japan, a deaf, volleyball-playing Japanese teenager (Rinko Kikuchi) is confused by her burgeoning sexual impulses. And in San Diego, a Mexican nanny (Adriana Barraza) has a problem: She wants to go to her son's wedding in Mexico, but she is watching her employers' kids. They were supposed to be back from their vacation in Morocco, but there's been some kind of accident. A shooting.

Brad Pitt and Cate Blanchett are the two big names in the cast, and they're at the center of the main action: Blanchett, as a middle-class San Diego woman, is the unlucky passenger who gets shot while riding the bus. The bus comes to a halt in a small Moroccan village, where she is brought into a house, bleeding profusely from neck and shoulder. Pitt, as her husband, frantically tries to contact the American Embassy and to get his wife emergency medical attention, but they're three hours away from the nearest hospital. Blanchett mainly just lies there, but the role is a good, if modest, showcase for Pitt, whose distress is quite convincing.

Unfortunately, the film's adherence to an arbitrary storytelling mannerism obligates it to cut from the life-and-death crisis in Morocco to banal scenes of the Japanese girl flirting with boys.

Think about it: One character is bleeding to death in Morocco. Do you really care if Chieko has a boyfriend -- or if the nice nanny gets to go to her son's wedding in Mexico? Moreover, should you?

For even if you can overcome a natural resistance to leave the dramatic for the banal, the movie offers no recompense for taking the journey.

Instead, by the end of 142 long minutes, it becomes clear that the Japanese thread had no place in this movie, and the Mexican thread, though more interesting and ultimately affecting on its own terms, probably didn't belong either.

Despite a sincere effort, "Babel" doesn't coalesce into some global vision but remains just four disparate stories, not one of them strong enough to hold up for an entire feature.

Yet with a little more investment and imagination, the story of the American tourists and of the Moroccan boys could have been combined into a stylistically honest, culturally observant picture.

-- Advisory: Nudity, gore, violence and strong language.

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